To law enforcement, automatic license plate readers are an effective tool for nabbing suspects, returning stolen cars and investigating murders.

Assisted by license plate reader technology, police can drive through parking lots, automatically checking license plates as they go. Readers can be placed in squads or fixed in place. (Photo by T.W. Budig)

Others view the technology, capable of capturing thousands of license plates per minute, as a potential electronic stalker.

Intimate activities of the innocent, as well as criminals, can be tracked, critics warn.

The use of automatic license plate readers isn’t limited to big cities. They’re in the suburbs, too.

The Washington County Sheriff’s Department uses two readers; the Bloomington Police Department has five squads equipped. Other suburban police departments, including the Inver Grove Heights and South St. Paul police departments in Dakota County, use license plate readers, as well. The Minnesota State Patrol also has a squad equipped with a reader.

Minnesota Sheriffs Association Executive Director Jim Franklin said, of law enforcement entities in the state, probably fewer than 20 departments are using the technology. But Minnesota Department of Public Safety Commissioner Ramona Dohman suggested that could grow.

“I would say there are probably some agencies holding off, waiting to purchase the technology until they have a better understanding what they actually can do with it,” Dohman said.

The number of license plates being read is huge.

According to Minnesota State Patrol records obtained by the ACLU, between January and November 2011, the patrol registered 752,293 plate reads. About 329 citations and 63 arrests were made.

Some law enforcement officials, including Dohman, argue license plate readers are effective.

The Bloomington Police Department used its readers to check vehicles in a neighborhood following a murder, said Bloomington Police Department Deputy Chief Vic Poyer, who said he thinks readers are effective as law enforcement tools.

Dakota County Attorney James Backstrom gave a spirited defense of the use of license plate readers.

“It is not an infringement of privacy,” Backstrom said, saying anyone can take pictures of license plates in public. Police for years have been jotting down plate numbers and entering them into computers, he said.

Lawmakers have been grappling with privacy issues relating to automatic license plate readers. How long law enforcement should retain license plate data and whether the information should be public or private are key concerns. (Photo by T.W. Budig)

As the result of a request to state officials by the city of Minneapolis, license plate numbers along with date, time and location data on vehicles, plus pictures of license plates, vehicles and areas surrounding the vehicles, as captured by readers, have been classified as private data.

The Democratic-led House last session passed legislation that does not permit retention of license plate data by law enforcement not linked to criminal activity. But the Democratic-led Senate did not act on license plate reader legislation.

House Civil Law Committee Chairman John Lesch, DFL-St. Paul, a prosecutor for the city of St. Paul, said law enforcement officials themselves are uncomfortable with amassing data on innocent people.